<template>
  <div class="custom-tree-container">
    <div class="block">
      <p>使用 render-content</p>
      <el-tree
        :data="data"
        show-checkbox
        node-key="id"
        default-expand-all
        :expand-on-click-node="false"
        :render-content="renderContent"
      >
      </el-tree>
    </div>
    <div class="block">
      <p>使用 scoped slot</p>
      <el-tree
        :data="data"
        show-checkbox
        node-key="id"
        default-expand-all
        :expand-on-click-node="false"
      >
        <span class="custom-tree-node" slot-scope="{ node, data }">
          <span>{{ node.label }}</span>
          <span>
            <el-button type="text" size="mini" @click="() => append(data)">
              Append
            </el-button>
            <el-button
              type="text"
              size="mini"
              @click="() => remove(node, data)"
            >
              Delete
            </el-button>
          </span>
        </span>
      </el-tree>
    </div>
  </div>
</template>

<script>
let id = 1000

export default {
  data () {
    const data = [
      {
        id: 1,
        label: '一级 1',
        children: [
          {
            id: 4,
            label: '二级 1-1',
            children: [
              {
                id: 9,
                label: '三级 1-1-1'
              },
              {
                id: 10,
                label: '三级 1-1-2'
              }
            ]
          }
        ]
      },
      {
        id: 2,
        label: '一级 2',
        children: [
          {
            id: 5,
            label: '二级 2-1'
          },
          {
            id: 6,
            label: '二级 2-2'
          }
        ]
      },
      {
        id: 3,
        label: '一级 3',
        children: [
          {
            id: 7,
            label: '二级 3-1'
          },
          {
            id: 8,
            label: '二级 3-2'
          }
        ]
      }
    ]
    return {
      data: JSON.parse(JSON.stringify(data))
    }
  },

  methods: {
    append (data) {
      const newChild = { id: id++, label: 'testtest', children: [] }
      if (!data.children) {
        this.$set(data, 'children', [])
      }
      data.children.push(newChild)
    },

    remove (node, data) {
      const parent = node.parent
      const children = parent.data.children || parent.data
      const index = children.findIndex((d) => d.id === data.id)
      children.splice(index, 1)
    },

    renderContent (h, { node, data, store }) {
      return (
        <span class="custom-tree-node">
          <span>{node.label}</span>
          <span>
            <el-button
              size="mini"
              type="text"
              on-click={() => this.append(data)}
            >
              Append
            </el-button>
            <el-button
              size="mini"
              type="text"
              on-click={() => this.remove(node, data)}
            >
              Delete
            </el-button>
          </span>
        </span>
      )
    }
  }
}
</script>

<style>
.custom-tree-node {
  flex: 1;
  display: flex;
  align-items: center;
  justify-content: space-between;
  font-size: 14px;
  padding-right: 8px;
}
</style>
